Results 251 to 260 of about 4,750,073 (297)

Construction of relations in relational databases

ACM Transactions on Database Systems, 1980
Using a nonprocedural language for query formulation requires certain automatization of a query answering process. Given a query for creation of a new relation, the problem is to find an efficient procedure which produces this relation from a given relational database. We concentrate upon sequences of join operations which losslessly produce a relation
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ASDViews (relational databases)

Proceedings. 1988 IEEE Symposium on Security and Privacy, 2003
A description is given of ASDViews, an implementation of views as the security object in a multilevel secure relational database management system (DBMS) that results in a small trusted computing base (TCB) as required to meet the criteria for evaluation class B2 and above. A general view is the result of a database query.
Cristi Garvey, Amy Wu
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Summarizing relational databases

Proceedings of the VLDB Endowment, 2009
Complex databases are challenging to explore and query by users unfamiliar with their schemas. Enterprise databases often have hundreds of inter-linked tables, so even when extensive documentation is available, new users must spend a considerable amount of time understanding the schema before they can retrieve any information from the database.
Yang, X., Procopiuc, C.M., Srivastava, D.   +2 more
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Fingerprinting relational databases

Proceedings of the 2006 ACM symposium on Applied computing, 2006
In this paper, we propose a fingerprinting solution to protect valuable numeric relational data from illegal duplications and redistributions. We introduce a twice-embedding scheme. In the first embedding process, we embed a unique fingerprint to identify each recipient to whom the relational data is distributed.
Fei Guo, Jianmin Wang 0001, Deyi Li
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Metaprogramming for Relational Databases

2004
For systems that share enough structural and functional commonalities, reuse in schema development and data manipulation can be achieved by defining problem-oriented languages. Such languages are often called domainspecific, because they introduce powerful abstractions meaningful only within the domain of observed systems.
Jernej Kovse, Christian Weber 0002, Theo Härder   +2 more
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On decomposition of relational databases

23rd Annual Symposium on Foundations of Computer Science (sfcs 1982), 1982
A central issue in relational database theory is that of decomposition. It has been agreed that decompositions should be injective, so as not to lose information, and surjective, so they decompose a relation into independent components. Injectiveness and surjectiveness are in general second-order notions.
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Entities and relations for historical relational databases

Proceedings of TIME '97: 4th International Workshop on Temporal Representation and Reasoning, 2002
Research to extend models of data to handle the temporal dimension has been conducted mainly in the context of the relational data model. In the relational model, the primary object of database design, manipulation and retrieval is the relation, viewed extensionally as a finite set of tuples. This paper proposes three useful types of temporal entities:
Robert A. Morris 0001, Lina Khatib
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Relational Scaling and Databases

2002
More than 20 years of theoretical development and practical experience in the field of Conceptual Information Systems have made available a wide variety of structure and procedures to gain new knowledge from data or to present it in a user-friendly way, by restructuring the data in a conceptual way to help the user interpret and understand the meaning.
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Watermarking Relational Databases

2002
We enunciate the need for watermarking database relations to deter their piracy, identify the unique characteristics of relational data which pose new challenges for watermarking, and provide desirable properties of a watermarking system for relational data.
Rakesh Agrawal 0001, Jerry Kiernan
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Equivalence of relational database schemes

Proceedings of the eleventh annual ACM symposium on Theory of computing - STOC '79, 1979
We investigate the question of when two database schemes embody the same information. We argue that this question reduces to the equivalence of the sets of fixed points of the project-join mappings associated with the two database schemes in question.
Catriel Beeri, Alberto O. Mendelzon, Yehoshua Sagiv, Jeffrey D. Ullman   +3 more
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